Classifications

• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07D—HETEROCYCLIC COMPOUNDS
  • C07D495/00—Heterocyclic compounds containing in the condensed system at least one hetero ring having sulfur atoms as the only ring hetero atoms
  • C07D495/02—Heterocyclic compounds containing in the condensed system at least one hetero ring having sulfur atoms as the only ring hetero atoms in which the condensed system contains two hetero rings
  • C07D495/04—Ortho-condensed systems
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07D—HETEROCYCLIC COMPOUNDS
  • C07D333/00—Heterocyclic compounds containing five-membered rings having one sulfur atom as the only ring hetero atom
  • C07D333/02—Heterocyclic compounds containing five-membered rings having one sulfur atom as the only ring hetero atom not condensed with other rings
  • C07D333/04—Heterocyclic compounds containing five-membered rings having one sulfur atom as the only ring hetero atom not condensed with other rings not substituted on the ring sulphur atom
  • C07D333/26—Heterocyclic compounds containing five-membered rings having one sulfur atom as the only ring hetero atom not condensed with other rings not substituted on the ring sulphur atom with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
  • C07D333/38—Carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
  • Y02P20/00—Technologies relating to chemical industry
  • Y02P20/50—Improvements relating to the production of bulk chemicals
  • Y02P20/582—Recycling of unreacted starting or intermediate materials

Definitions

• the invention relates to a process for the thermal decarboxylation of dicarboxylic acids, in particular the decarboxylation of dialkoxythiophene and
• Alkylenedioxytiophene-dicarboxylic acids without the addition of an additional solvent, possibly with the addition of an inert gas.
• Inert gases in the sense of this invention are gases which do not react with the dicarboxylic acid under the conditions used.
• the conditions used in these ner drives are mostly based on the thermal instability of the connections.
• the decarboxylation is advantageously carried out in a solvent with the addition of a catalyst which accelerates the decarboxylation.
• the starting material In addition to the 3,4-ethylenedioxythiophene-2,5-dicarboxylic acid, however, the starting material always contains small amounts of by-products which are formed in previous synthesis steps. These by-products accumulate in the solvent and limit the reusability of the solvent and catalyst. Cu-containing wastes are formed which have to be disposed of in a complex manner.
• the process described for the decarboxylation of 3,4-ethylenedioxythiophene-2,5-dicarboxylic acid which represents the prior art, can only be operated in batches. In the case of purely thermal decarboxylation, a large part of the product remains in the reaction space and, as a result of the elevated temperatures, there is an increased formation of by-products which severely impair the quality or which make expensive post-cleaning necessary.
• the object of the present invention is to provide a procedure for the decarboxylation of 3,4-ethylenedioxythiophene-2,5-dicarboxylic acid and the like
• the invention by which the object is achieved, is a process for the thermal decarboxylation of dicarboxylic acids, in particular 3,4-ethylenedioxythiophene-2,5-dicarboxylic acid as starting material, characterized in that the starting material is used as a solid and / or the Carrying out reaction in the presence of a large number of fluidized bed bodies, the reaction being carried out in the absence of solvents and the resultant product of the reaction
• Decarboxylation product in particular the 3,4-ethylenedioxythiophene, is removed in gaseous form from the reaction zone.
• the decarboxylation is preferably carried out at a temperature of 100 to 600 ° C., preferably 100 to 500 ° C., particularly preferably 150 to 400 ° C.
• Educt solid can be obtained. It was found that the 3,4-ethylenedioxythiophene formed has a sufficiently high vapor pressure at the temperature required for decarboxylation to be discharged in gaseous form with an inert gas stream and can be separated off by cooling. In this way, the use of operating materials is minimized and continuous or quasi-continuous operation is made possible.
• the process according to the invention can be carried out in various types of reactor, as long as the product formed by the decarboxylation, e.g. 3,4-ethylenedioxythiophene, is discharged in gaseous form from the reactor.
• the product formed by the decarboxylation e.g. 3,4-ethylenedioxythiophene
• the process is in particular carried out continuously in a bubble-forming, or turbulent or irradiated fluidized bed, or in an internally or externally circulated fluidized bed.
• the reaction is particularly preferably carried out in the presence of an inert auxiliary gas, in particular selected from the series of noble gases, nitrogen, water vapor, carbon monoxide or carbon dioxide or a mixture of various such inert auxiliary gases.
• an inert auxiliary gas in particular selected from the series of noble gases, nitrogen, water vapor, carbon monoxide or carbon dioxide or a mixture of various such inert auxiliary gases.
• gases which do not react with the starting material or product under the chosen reaction conditions are suitable as inert gases; suitable inert gases are, for example, noble gases, nitrogen, water vapor, carbon monoxide or carbon dioxide. It is possible to carry out the process according to the invention for the decarboxylation of 3,4-ethylenedioxvthiophene-2,5-dicarboxylic acid with the addition of an inert gas or a mixture of several inert gases in any combination.
• the temperature can be varied from 100 ° C to 600 ° C as described. However, it must be so high that the decarboxylation of the starting material e.g. of 3,4-ethylenedioxythiophene-2,5-dicarboxylic acid is guaranteed and must not exceed the decomposition temperature of 3,4-ethylenedioxythiophene-2,5-dicarboxylic acid or 3,4-ethylenedioxythiophene.
• the starting material e.g. of 3,4-ethylenedioxythiophene-2,5-dicarboxylic acid is guaranteed and must not exceed the decomposition temperature of 3,4-ethylenedioxythiophene-2,5-dicarboxylic acid or 3,4-ethylenedioxythiophene.
• the reaction is preferably carried out in a fluidized bed or fluidized bed reactor in which fluidized bed bodies are used with an average diameter (number average) which is larger than the particle diameter of the dicarboxylic acid.
• the fluidized bed bodies particularly preferably have a solids density p s of
• the fluidized bed bodies can also preferably be used as heat transfer media which are preheated outside the reaction zone and circulated through the reaction zone.
• the fluidized bed bodies preferably consist partially or entirely of a catalytically active material, in particular copper or a copper salt, preferably of CuCO 3 .
• the process according to the invention is preferably carried out in a fluidized bed.
• solid particles of 3,4-ethylenedioxythiophene-2,5-dicarboxylic acid, hereinafter referred to as particles are placed in the reaction chamber.
• the particles can be supplied batchwise or continuously from the outside.
• the particles form a fixed bed through which the added gas flows.
• the inflow rate of the supplied gas can be adjusted so that the fixed bed is fluidized and a fluidized bed is formed.
• the corresponding procedure is known per se to the person skilled in the art.
• the inflow speed of the supplied gas must at least correspond to the loosening speed (also the minimum fluidization speed).
• Loosening speed is understood to mean the speed at which a gas flows through a bed of particles and below which the fixed bed is retained, ie below which the bed particles remain largely stationary. Above this speed the fluidization of the bed begins, ie the bed particles move and the first bubbles form.
• the gas velocity is selected so that it corresponds to one to ten times the loosening velocity, preferably one to seven times, particularly preferably one to five times.
• the starting material 3,4-ethylenedioxythiophene-2,5-dicarboxylic acid into a bed of larger particles. If the average particle size of the 3,4-ethylenedioxythiophene-2,5-dicarboxylic acid is 0.1-50 ⁇ m, for example, then the average particle size of the 3,4-ethylenedioxythiophene-2,5-dicarboxylic acid is 0.1-50 ⁇ m, for example, then the average particle size of the 3,4-ethylenedioxythiophene-2,5-dicarboxylic acid is 0.1-50 ⁇ m, for example, then the average particle size of the 3,4-ethylenedioxythiophene-2,5-dicarboxylic acid is 0.1-50 ⁇ m, for example, then the average particle size of the 3,4-ethylenedioxythiophene-2,5-dicarboxylic acid is 0.1-50 ⁇ m, for example, then the average particle size of the 3,4-ethylenedioxythiophene-2,5-dicarboxylic
• Pulse and heat transfer media serve and / or all or part of one exist catalytically active material.
• metals, metal oxides or metal salts can be used as catalytically active materials. Copper, copper oxides and copper salts are particularly preferably used. Solid materials can be used, but the active components can also be mixed or applied with a carrier. The use of pure
• Educt 3,4-ethylenedioxythiophene-2,5-dicarboxylic acid can be introduced, for example, via screws, hijectors or a lock system. Another form of entry can be injecting melted or solvent-diluted 3,4-ethylenedioxythiophene-2,5-dicarboxylic acid.
• a catalyst can be introduced in pure form, as a mixture or in supported form in the form of internals in the reactor.
• Rigid or flexible internals, rod and tubular internals, constructions in the form of perforated plates, nets, grids or three-dimensional are mentioned as examples
• the separation of finely divided educt solids from the gas stream leaving the reactor can be carried out, for example, using a cyclone, a filter or a
• Gas scrubbers take place. Separation via a cyclone and / or a filter is preferred.
• the collected educt solid is advantageously returned to the decarboxylation sctt. This return can take place, for example, through an internal or external circulation. However, the return can also be done by blowing back and cleaning filters.
• a preferred method is characterized in that any solid discharged from the reaction zone by the gas stream is separated from the product using a cyclone and / or filter. Also preferred is a variant of the process in which unreacted educt solids separated from the product gas stream are batchwise or continuously returned to the reaction zone becomes.
• Nitrogen stream (normal conditions) heated to a maximum reaction temperature of 320 ° C (heating rate 2 ° C / min). The starting material was reacted off over a period of 100 min. 32.0 g (0.139 mol) of the amount of raw material were reacted. 16.6 g of product were condensed out in a downstream cold trap. The 3,4-ethylenedioxythiophene content was> 94% by weight.

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• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
• Heterocyclic Carbon Compounds Containing A Hetero Ring Having Oxygen Or Sulfur (AREA)

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• 2002
  • 2002-12-16 DE DE10258588A patent/DE10258588A1/de not_active Withdrawn
• 2003
  • 2003-12-04 KR KR1020057011049A patent/KR101057890B1/ko not_active IP Right Cessation
  • 2003-12-04 JP JP2004559751A patent/JP4695880B2/ja not_active Expired - Fee Related
  • 2003-12-04 EP EP03780117A patent/EP1575961B1/de not_active Expired - Lifetime
  • 2003-12-04 CN CNB2003801062452A patent/CN100338070C/zh not_active Expired - Fee Related
  • 2003-12-04 US US10/538,995 patent/US7671217B2/en not_active Expired - Fee Related
  • 2003-12-04 AT AT03780117T patent/ATE365168T1/de active
  • 2003-12-04 DE DE50307534T patent/DE50307534D1/de not_active Expired - Lifetime
  • 2003-12-04 WO PCT/EP2003/013679 patent/WO2004055023A1/de active IP Right Grant
  • 2003-12-04 AU AU2003288225A patent/AU2003288225A1/en not_active Abandoned

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